Author Topic: Ideal air pressure to maintain in my tires  (Read 18762 times)

Steve Huber

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Re: Ideal air pressure to maintain in my tires
« Reply #15 on: September 22, 2012, 10:49:47 PM »
My mistake, I thought they would give you 4 corner weight. I had mine weighed at a Freight-liner Service shop. It gave 4 corner results.
Steve
Steve
Coachless
2015- 6/24  07 Contessa Bayshore C9,  400 hp
2013-2015: 00 Marquis Tourmaline, C12, 425 hp
2005-2013: 01 Contessa Naples, 3126B, 330 hp

Richard Cooper

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Re: Ideal air pressure to maintain in my tires
« Reply #16 on: September 23, 2012, 12:32:15 AM »
I currently have 115 psi in all tires.

Steve Huber

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Re: Ideal air pressure to maintain in my tires
« Reply #17 on: September 23, 2012, 01:09:40 AM »
If you want a good ride, it's important to use the tire mfgr's recommendations based on your 4 corner weight. I thought that I needed to run 115-120PSI  but after weighing and consulting Goodyear's table, I found that I should be running about 95PSI. It obviously improved the ride and wear has been normal after about 50K miles.
Steve
« Last Edit: September 23, 2012, 10:58:43 PM by 14 »
Steve
Coachless
2015- 6/24  07 Contessa Bayshore C9,  400 hp
2013-2015: 00 Marquis Tourmaline, C12, 425 hp
2005-2013: 01 Contessa Naples, 3126B, 330 hp

Keith Oliver

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Re: Ideal air pressure to maintain in my tires
« Reply #18 on: September 23, 2012, 04:18:52 AM »
As Larry said about Oregon, Highways Dept scales are left on in BC, when the sign out on the highway says "closed".  I had my wife move the orange cone so I could drive one side on, then when I was through she put the cone back.  I had already weighed the full axles, so now I know the individual corner weights, and one side of the toad.  Simple math does the rest.

Larry and Heidi Lee

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Re: Ideal air pressure to maintain in my tires
« Reply #19 on: September 24, 2012, 11:03:16 PM »
I just had the identical Michelin 295/80R 22.5 XZA2 Energy LRH installed am surprised to find my tire pressures are all over the place based on the Michelin inflation charts for RV use only (MWL43146 4.2009).

My weight is as follows:
RF: 5200
LF: 5320
RR in: 10960
RR out: 10960
LR in: 9840
LR out: 9780

Based on the Michelin inflation chart the recommended presses should be as follows:

Front: 75 psi
Rear: 90 psi

If anyone can think of something I am missing here please let me know.

Very odd, the tire dealer set my pressures (3 days ago and have been siting here cold the entire time) to:

RF 91
LF 98
RRI 92
RRO 91
LRI 92
LRO 97

This completely baffles me and think that the technician did not know what he was doing. Somebody please tell me I am correct.











Joel Ashley

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Re: Ideal air pressure to maintain in my tires
« Reply #20 on: September 24, 2012, 11:49:45 PM »
Is the sun on your left side?  It can heat up a black tire so the pressure is a bit different than the shade side tires.

And I don't know, but I'd think 75psi is a pretty low recommendation for any of our coaches.

Joel
Joel and Lee Rae Ashley
Clackamas, Oregon
36.9 ft. 2006 Monterey Ventura IV, aka"Monty Rae"
C9 400HP Cat

Larry and Heidi Lee

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Re: Ideal air pressure to maintain in my tires
« Reply #21 on: September 25, 2012, 01:16:42 AM »
Joel, check out this Michelin inflation table for the 295/80R 22.5 xza2
http://www.michelinrvtires.com/michelinrv/tires-retreads/load-inflation-tables.jsp

Based on my weights above...

Now that the sun has gone down I checked the driver side again and the outside tire pressures have dropped by 2 psi.

Tom and Pam Brown

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Re: Ideal air pressure to maintain in my tires
« Reply #22 on: September 25, 2012, 01:52:18 AM »
I find it interesting all the angles to tire pressures.  After 25 plus years in the trucking industry I cannot imagine every load being weighed and tire pressures being adjusted.  

My personal thought are to adjust to the weight of the coach front and rear and leave it alone.  There is no way to load the coach to a weight that would require an air adjustment.  Assuming of course you weigh the coach like you travel with fuel, water and accessories.  

My opinion is that would be all that is required.  And speaking with the professionals in the industry they kinda giggle a bit over the over thinking.

Having said all of that I encourage all to do what they think is the safest for their situation.  I run 110 psi in all my tires and it performs well and rides great.  By the way that is exactly where it should be based on the weight of my coach, front and rear.

Travel and be safe.

LarryNCarolynShirk

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Re: Ideal air pressure to maintain in my tires
« Reply #23 on: September 25, 2012, 06:07:17 AM »
Larry Lee,

From the table you referenced, your fronts should be at 75 pounds, and the backs should be at 90 pounds, when out of the sun and with the ambient temperature at 70 degrees.  

Trust your scales and enjoy the comfortable ride.

Larry

Larry and Heidi Lee

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Re: Ideal air pressure to maintain in my tires
« Reply #24 on: September 25, 2012, 06:49:47 PM »
Thanks Larry, this is what I needed to hear. I need to trust the Michelin recommendations.